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<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    <script>
        function Person (name){
            this.name=name;
        }
        Person.prototype={
            constructor:Person,
           sayHi:function(){
               console.log('这是原型对象上的说话方法');
               
           }
        }
        var p1 = new Person('jack');
        p1.sayHi();
        p1.sayHi = function(){
            console.log('这是新的方法');
            
        }
        p1.sayHi();
        var p2 = new Person('andy');
        p2.sayHi();

    </script>
</body>
</html>